This paper derives from a study undertaken at an emergency service centre in Sweden. The studies have focused on fea-tures of work familiar to the CSCW community, including the documenting and analysing current work practices, un-derstanding the properties of the technology in question, and perhaps most importantly how the technology func-tions in and through use. Our focus in this paper exempli-fies these themes through the analysis of two cases. In the first, the issue in question is the way in which an emer-gency is identified and dealt with, it being the case that a typical problem to be dealt with by operators, and more commonly in the days of mobile telephony, is that of mul-tiple reporting of a single case. Of particular interest here is listening-in, which is a function in the Computer Aided Dispatch (CAD) system and by contrast that of ?overhear-ing?, which is not. The second case focus on the relevance of wall maps, given the existence of computerized maps in these centres. Based on two cases from emergency service centres, we will show that the concept of awareness needs careful unpacking if we are to understand associated design issues.